Why is it impossible while 5m or more below water to breathe through a hose connected to the surface air, but easy to breathe through a scuba?

Question

Why is it impossible while 5m or more below water to breathe through a hose connected to the surface air, but easy to breathe through a scuba?

In: 158

Answer 1

The regulator on the scuba tank, puts out air at the exact pressure that a diver is under. That is why you never hold your breath while ascending or you blow up your lungs.